The present invention relates to a system for equilibrating an imbalance couple, the use thereof for equilibrating an airborne radar antenna and an antenna equilibrated by such a system.
Some mechanisms driven with a rotational movement are sometimes subjected to variable accelerations. When they are placed in cantilever relation with respect to the rotational axis, the imbalance thus created must be equilibrated.
This is in particular the case with an airborne radar antenna which is orientatable along three orthogonal axes. The axis carrying the antenna must house elements such as motors, angle recopying elements or rotary joints. The antenna is then placed in complete cantilever relation with this axis. The cantilever is often very great and may reach fifteen centimeters for large antennae.
During a banking turn or when pulling out from a dive, the carrier plane may impose on the antenna load factors reaching 10 g. The mass of the antenna and consequently the imbalance couple, when it is not equilibrated, are multiplied by this factor. The imbalance may then exceed the maximum possible drive torque.
In the prior art, a part rotating about an axis is balanced by means of masses carried by the securing device of the mobile part opposite said part with respect to the axis of rotation considered. The balancing masses may be troublesome, either because of their very mass which is added to the mass of the rotating mechanism or because of their volume which limits the amplitude of the rotational movement.